1. Field of the Invention
This invention relates generally to touchpads. More specifically, the present invention is a method for creating a plurality of discrete zones or regions in a border region of a touchpad, wherein a scrolling zone and edge motion are both controlled by finger location, not finger motion, wherein placing a finger in specific zones is used to control speed of scrolling within a graphical window, and the angle of automatic edge motion of a cursor in a graphical user interface.
2. Description of Related Art
To understand the advantages and differences of the present invention as compared to the prior art, this document first examines the prior art of edge motion and of scrolling.
Beginning with edge motion, in U.S. Pat. No. 5,327,161, Logan teaches a touchpad having a form of edge motion. FIG. 1 is a diagram that illustrates the main concept of the patent. A finger moves along the surface of the touchpad 10 along the line indicated as 12, thereby controlling movement of a cursor on a graphical user interface. When the finger reaches a border region 14, the touchpad determines a direction of movement (indicated as dotted line 16) of the finger as it entered the border region. The user can stop movement of the finger in the border region 14, and the cursor will continue movement in the direction 16 determined by the touchpad 10 when the finger first entered the border region until the user removes the finger from the surface of the touchpad, or moves the finger out of the border region.
In U.S. Pat. No. 5,880,590, Gillespie et al. teaches a modification of the Logan method. Specifically, a fixed reference point 22 is established on the touchpad 20 as shown in FIG. 2. When the user moves a finger across the surface (as indicated by solid line 24) of the touchpad 20 and enters a border region 24, a vector is determined by the touchpad. However, instead of determining the vector relative to the direction of movement of the finger as it enters the border region as in Logan and indicated by dotted line 26, the vector is taken from the fixed reference point 22 and the location 28 where the finger enters the border region 24. In this example, the direction of movement of the cursor would thus be in the direction indicated by dotted line 30. It can be seen that while different from Logan, the direction of continued movement of the cursor is relatively more difficult for a user to determine until movement of the cursor actually begins because continued movement is no longer determined by the last known direction of movement of the finger. Thus, the '590 patent does not use the more intuitive direction of continued cursor movement as taught by Logan.
In U.S. Pat. No. 5,880,411, also issued to Gillespie et al., the '411 patent teaches still another method that is different from the Logan method and the method of the '590 patent. Specifically, the '411 patent teaches that a finger on a surface of a touchpad 40 enters a border region 42 as shown in FIG. 3. However, instead of determining any vector, a cursor will simply move in a direction that is orthogonal to the edge of the touchpad 40 as indicated by dotted line 44. In other words, the cursor in this example would move in a horizontal direction straight toward the right edge of a graphical display because the finger entered a right border region 42 of the touchpad 40. This method is known as orthogonal edge motion.
The '411 patent also teaches being able to modify the movement of the cursor. Consider the example of FIG. 4 where the cursor is moving in the direction indicated by dotted line 44 of FIG. 3. If the user's finger moves first in the direction indicated by arrow 48 in a vertical direction, the horizontal movement of the cursor continues, but now has added to it a vertical component that follows the motion of the user's finger. This horizontal and vertical movement is indicated as upwardly sloping segment 52 of the cursor movement. If the finger momentarily stops, the cursor movement levels out as indicated by level segment 54 of the cursor movement. When the finger moves in the direction and magnitude of arrow 50, the cursor movement follows downward sloping segment 56. The cursor movement follows level segment 58 when the finger stops vertical movement.
Some helpful observations about how the border regions operate in the '161, the '590, and the '411 patents are as follows. The '411 patent teaches that regardless of what vector the finger has when entering the border region, the cursor moves orthogonally relative to the border region that has bee entered. There is no other option but to move orthogonally. In addition, the '411 patent teaches that vertical movements of the cursor are controlled by determining a previous position of the finger in the border region, and a present position. This realization is important to understanding the differences between the prior art and the present invention.
FIG. 5 illustrates the concept that if the finger is at a first position 60 and moves to a second position 62 in a border region 64, corresponding movement of the cursor on the graphical display will be a vertical component of movement in the same direction. Critically, when the finger stops, the cursor will eliminate any vertical component of movement, but continue its horizontal movement. In other words, the vertical cursor movement is directly dependent upon movement in the vertical direction within the border region 64. This is because the '411 patent teaches that motion is the determining factor for adding a vertical component of cursor movement. In other words, the actual position or location of the finger in the border region is only important in being able to determine that movement is taking place. Accordingly, as long as movement is detected, cursor movement is modified.
The discussion above is focused on the issue of edge motion. In other words, edge motion addresses the issue of how cursor movement is modified when a finger enters a border region. In contrast, the following discussion is centered on the concept of scrolling. For the purposes of this patent, scrolling is defined as controlling horizontal or vertical movement within a window on a graphical user interface by receiving signals from a touchpad.
Scrolling is another element that exists in the prior art of touchpads. In U.S. Pat. No. 5,943,052 issued to Allen, the Allen patent teaches a scrolling region 70 on touchpad 68 as shown in FIG. 6. Vertical movement 72 within the scrolling region 70 results in scrolling within a graphical user window in a graphical user interface shown on a display screen. What is important to observe is that Allen teaches that a data packet processor generates messages in response to “object motion.” Object motion is apparently not dependent upon the location or position of a finger in the scrolling region 70. Instead, object motion is again dependent upon simply determining that motion is taking place, and then causing corresponding vertical (or horizontal) movement of the contents of the window.
It is important to understand the implications of this limitation of Allen. First, if movement of the finger causes scrolling action to occur, terminating movement of the finger likewise requires that scrolling must stop. Second, scrolling is not location dependent. In other words, scrolling action is not determined by where the finger is located within the scrolling region, it is only dependent upon whether or not the finger is moving, and in which direction the finger is moving.